Pre-gapped breaker point assemblies

ABSTRACT

A pre-gapped breaker point assembly for use with distributors of internal combustion engines including a contact arm, with a cam follower and breaker contact points, adapted for reciprocatory movement in consonance with the cam follower, and a novel spacing block, adapted to make contact with the distributor cam lobes, thereby establishing the distance the movable contact point separates from the stationary contact point in response to the rotating cam lobes moving the cam follower.

United States Patent 11 1 Clark PRE-GAPPED BREAKER POINT ASSEMBLIES [76]Inventor; William E. Clark, P.O. B651 702,

Pinedale, Wyo. 82941 [22] Filed: Apr. 30, 1973 [21] Appl. No.: 356,062

[52] US. Cl 200/31, 200/31 DP [51] Int Cl. H0lh 19/62 [58] Field ofSearch 200/16, 30 R, 30 A, 31 R,

200/31 A, 31 DP, 3] N [56] References Cited UNITED STATES PATENTS I I1,267,671 '5/1918 :Lang 200/3111 Sept. 3, 1974 Russell 200/31 A Bettoni200/31 A Primary Examiner-James R. Scott [57] ABSTRACT A pre-gappedbreaker point assembly for use with distributors of internal combustionengines including a contact arm, with a cam follower and breaker contactpoints, adapted for reciprocatory movement in consonance with the camfollower, and a novel spacing block, adapted to make contact with thedistributor cam lobes, thereby establishing the distance the movablecontact point separates from the stationary contact point in response tothe rotating cam lobes moving the cam follower.

4 Claims, 10 Drawing Figures l PRE-GAPPED BREAKER POINT ASSEMBLIES Thisinvention relates generally to breaker point assemblies for distributorsof internal combustion engines, and more particularly to the addition ofa novel spacing block which provides the means whereby the opening ofthe opposing breaker contact points to a spring biased movable arm and astationary bracket,

each provided with a contact point, all supported on a breaker platewithin the distributor.

In setting a conventional breaker point assembly, during installation ina distributor, for the proper distance the opposing breaker contactpoints will separate, the cam onthe distributor shaft is rotated to apofollower attached to the movable contact arm. Then, the stationarycontact point is adjustably positioned so that a predetermined distancewill exist between the opposing contact points. The installationprocedure for sition with one of its high points engaged with the caminstalling pre-gapped breaker pointassemblies is greatly simplified byeliminating the requirement to set the proper distance the opposingcontact points separate.

The primary object of this invention is to provide a means whereby theprocedure for installing a breaker point assembly in a distributor forinternal combustion engines will be greatly simplified by eliminatingthe need to set the distance the opposing breaker contact pointsseparate when the engine is running.

A more specific object of this invention is to provide a pre-gappedbreaker point assembly, for use in a distributor for internal combustionengines, incorporating a novel spacing block whereby the distance theopposing breaker contact points are set to separate during manufacturewill coincide with that distance the opposing breaker contact pointsseparate when the pregapped breaker point assembly is installed in adistributor and the engine is' running.

A further object of this invention is to provide a means ofconstruction, wherein the normally stationary breaker contact point onthe breaker point assembly may be readily adjusted relative to themovable breaker contact point.

Another object of this invention is to provide an improved andsimplified construction in breaker point assemblies, wherein theconstruction is readily adapted to be installed in distributors incommon usage nal combustion engines. I A final object of this inventionis to provide a breaker point assembly icorporating a spacing block thatmay be removed after the breaker point assembly is installed in adistributor. v

I .With the foregoing and other objects in view, this invention residesin the'following specifications and appended claims, certain embodimentsand details of construction of which are illustrated in the accompanyingdrawings in which:

FIG. I is a top plan view of a conventional type of ignition distributorshownwith the pre-gapped breaker point assembly of the instant inventionmounted therein; g

with inter-.

FIG. 2 is a side elevational view of the pre-gapped breaker pointassembly illustrated in FIG. 1;

FIG. 3 is a top plan view of a portion of a conventional type ofignition distributor shown with a modified form of the pre-gappedbreaker point assembly mounted therein;

FIG. 4 is a side elevational view of the pre-gapped breaker pointassembly illustrated in FIG. 3;

FIG. 5 is a side elevational view of a portion of the stationary uprightflange showing the adjustable threaded body and contact point;

FIG. 6 is a top plan view of the stationary upright flange and a portionof the breaker point base showing the elongated adjustment slot andcontact point;

FIG. 7 is a perspective view of the novel spacing block illustrated inFIGS. 1 and 2 showing a two-piece means of construction;

FIG. 8 is a top plan view of a modified form of the I novel spacingblock;

,FIG. 9 is a perspective view of a modified form of the novel spacingblock;

FIG. 10 is a perspective view of a modified form of the novel spacingblock.

Referring now more specifically to the drawings, the numeral 1designates a conventional distributor housing having a breaker plate 2mounted therein for movement about the axis of rotation of cam 3 whichis centrally disposed relative to breaker plate 2. A conventional vacuumadvance assembly generally referred to by the numeral 4 is provided andis pivotally secured to breaker plate 2 by means of pivot pin 5. Acondenser 6 is attached to breaker plate 2 bymeans of screw 7, and itslead 8 is connected to terminal post 9 by nuts 10. Electrical lead 1 1is connected similarly to terminal post 9 and continues to housingoutlet grommet l2. Cam 3 extends through circular cutout 40 in breakerplate 2 and contains rotor retainer 39 as its top member.

The pre-gapped breaker point assembly of the instant invention isgenerally referred to by numeral and includes a movable contact arm 21and contact point 22 resiliently urged toward upright stationary flange23 and contact point 24 by spring 25. Rotation of cam 3 causes insulatedcam follower 26 to engage various cam lobes 27 resulting in contactpoint 22 alternately opening a specific and repeatable distance from,and then closing against, contact point 24. Contact arm 21 is pivotallysupported by pivot post 28, and spring is secured at one end to contactarm 21 and at the other end to terminal post 9 which is positioned byupright posts 30A and 30B, and insulated therefrom by ushaped insert 31Aand 31B. Breaker point assembly 20 is attached to breaker plate 2 byscrews 32 and 33 which extend through elongated adjustment slots 34 and35 into threaded bores in breaker plate'2. Cutout 36 in breaker plate 2is an aid for conventional adjust ment of contact points. Grounding lead37 is attached to breaker point assembly 20 byscrew 32 and to breakerplate 2 by screw 38. t

The novel spacing block shown in FIGS. 1 and 2 is generally referred toby numeral 41. A specific shape of the spacing block for use with aspecific type of,

breaker point assembly will be determined during manufacture so that itwill not interfere with the operation of contact arm 21 nor withattaching screws 32 and 33. Many shapes and combinations are possiblewithin the scope and spirit of this invention. Likewise, the radius,

length, and heighth of abutment surface 42 will be determined for eachapplication during manufacture. Further, the material from which thespacing block is made may vary considerably, but preferably will beplastic, impregnated resin, or other suitable material which has surfacehardness qualities somewhat less than the distributor cam lobes 27.

During manufacture of pre-gapped breaker point assembly 20, correctpositioning of novel spacing block 41 is readily achieved by attachingthe breaker point assembly to a jig fixture simulating breaker plate 2and cam lobes 27, then adjusting spacing block 41 within the limitsprovided by elongated slots 45 and 46 to achieve exact coincidence-ofsimulated cam lobe 27, cam follower 26, and abutment surface 42 whilesimultaneously opening contact points 22 and 24 to an exactpredetermined distance. Tightening screws 43 and 44 preserves thisrelationship intact.

Installation of pre-gapped breaker point assembly 20, containing novelspacing block 41 correctly positioned thereon, in an ignitiondistributor, is accomplished by placing abutment surface 42 securelyagainst cam lobes 27, and adjustably positioning breaker point assembly-so that screws 32 and'33 can be installed through elongated slots 34and 35 into threaded bores in breaker plate 2. Tightening screws 32 and33 maintains this position. 1

Referring to FIGS. 3 and 4, an embodiment of the instant invention isillustrated wherein a modified form of the novel spacing block,generally referred to by the numeral 51, is attached by screws 53 and 54extending through spacers 55 and 56 and into threaded bores in breakerpoint assembly 90, which is substantially similar to breaker pointassembly 20 illustrated in FIGS. 1 and 2. Circular housing 57surroundscam 3 and abutment surface 52'contacts cam lobes 27 as shown.It is readily seen that correct positioning of spacing block 51 onbreaker point assembly 90 is accomplished in substantially the samemanner in which spacing block 41 was correctly positioned on breakerpoint assembly 20 above. Likewise, installation of breaker pointassembly 90 in a distributor is accomplished in substantially the samemanner in which breaker point assembly 20 was installed l-lowever,spacing block 51'may be removed after breaker point assembly 90 iscorrectly positioned and securely fastened to breaker plate 2 byexstruction is that the spacing block may be readily removed after thebreaker point assembly is correctly installed and securely fastened tothe distributor breake plate.

With attention now directed to FIG. 8, there will be seen a furthermodified form of spacing block referred to by numeral 70, incorporatingan upright curved abutment surface 71, a cutout 72 which allows the camfollower to operate therein without interference, another upright curvedabutment surface 73, and a deeply scribed or break line 74. Thismodified form of spacing block is substantially identical in function tospacing block 41, and is correctly positioned on the breaker pointassembly in a similar manner. However, spacing block 70, incorporatingbreak line 74, may be readily removed after the breaker point assemblyis correctly installed and securely fastened to the distributor breakerplate.

With attention now directed to FIG. 9, there will be seen a furthermodified form of spacing block referred to by numeral 75, incorporatingabutment surface 76, attaching holes 77 and 78, and break lines 79 and80. This modified form of spacing block issubstantially identical infunction to" spacing block 51; however, spacing block 75 may be'attachedto the breaker point assembly by rivets or other permanent means beforeit is correctly positioned thereon. In order to achieve the requiredopening of the contact points to their predetermined distance, on abreaker point assembly incorporating spacing block 75 or other spacingblock similarly attached, the normally stationary contactpoint must beconstructed, FIGS. 5 and 6 illustrate said construction means, so thatthe stationary contact point tracting screws 53 and 54 and liftingspacing block 51 from breaker point assembly 90.

With attention now directed to FIGS. 5 and 6, there will be seen twoalternate methods for adjusting the normally stationary contact point 24relative to the movable contact point ln FIG. 5, upright stationaryflange 23 is threaded with contact body 60 formed with adjustment slot61 to rotationally position contact point 24 nearer to or further fromstationary flange 23. In FIG- 6, stationary flange 23 is formed withbody extension 63 containing elongated slot 64 and attaching screw 65mounted on breaker point base 66. Adjust ment is readily apparent.

With attention now directed to FIG. 7, there will be seen a modifiedform of the spacing block referred to by numeral 41, illustrated inFIGS. 1 and 2, in which the spacing block is assembled from two.portions 68 and 69. A tongue and groove method of joining the twoportions is shown by joining line-67; however, any one of many suitableknown joining methods may be employed. The advantage of this modifiedform of conmay be adjustably positioned to achieve the opening of thecontact points to their predetermined distance at coincidence of a firstsimulated cam lobe with the cam follower and another simulated cam lobewith abutment surface 76. Break lines 79 and 80 provide the meanswhereby spacing block may be removed after the breaker point assembly iscorrectly installed and securely fastened to the distributor breakerplate.

With attention now directed to FIG. 10, there will be seen a furthermodified form of spacing block referred to by the numeral 81,incorporating surrounding abutment surface 82, cutout 83 that allows thecam follower to operate therein without interference, and break lines 84and 85. Spacing block 81 is substantially identical in function, meansof attachment, and ease of removal to the spacing blocksdescribedabove.

It is thus seen that the invention provides a simplified, economical,efficient, and improved manner inwhich the breaker point assembly may beinstalled in a distributor. It is readily realized that certain obviousother modifications in structure are possible to the construction of thepresent invention, and-it is intended thatthe scope thereof only bebound'by the scope of the appended claims. It is also obvious thatvarious distributor designs might requirecertain design. changes in thestructure of the invention in order to readily adapt the frame adaptedto be adjustably. mounted on said mounting plate and having a firstbreaker contact point secured to a stationary upright flange on saidframe and in electrical contact with said frame and said mounting plate,a second breaker contact point mounted on an arm which is pivotallysecured to said frame and resiliently urged to place said second breakercontact point in a normal contacting relationship with said firstbreaker contact point, a cam follower operable between said cam and saidarm and operable to intermittently separate said first and said secondbreaker contact points coincident with a high point on said cam andbeing resiliently urged toward said cam by said arm, and a spacing blockcomprised of an abutment surface adapted to bear against at least twohigh points of said cam and having adjustment means adapted to establishmaximum separation of said first and said second breaker contact pointsat coincidence of said cam follower with a high point on said cam, saidadjustment means comprising elongated mounting slots in said spacingblock structure.

2. The combination of claim 1 wherein said spacing block is removedafter said pre-gapped breaker point assembly is secured to saiddistributor movable mounting plate.

3. A pre-gapped breaker point assembly for use in a distributor for anignition system of an internal cornbustion engine and adapted to bemounted in a casing on a movable mounting plate secured in said casingto thereby cooperate with a cam operable by said engine, said pre-gappedbreaker point assembly comprising a frame adapted to be adjustablymounted on said mounting plate and having a first breaker contact pointsecured to a stationary upright flange on said frame and in electricalcontact with said frame and said mounting plate, a second breakercontact point mounted on an arm which is pivotally secured to said frameand resiliently urged to place said second breaker contact point in anormal contacting relationship with said first breaker contact point, acam follower operable between said cam and said arm and operable tointermittently separate said first and second breaker contact pointscoincident with a high point on said cam and being resiliently urgedtoward said cam by said arm and a spacing block comprising an abutmentsurface adapted to bear against at least two high points on said cam tothereby establish maximum separation of said first and said secondbreaker contact points at coincidence of said cam follower with a highpoint on said cam. I

4. The combination of claim 3 wherein said spacing block is removedafter said pre-gapped breaker point assembly is secured to saiddistributor movable mounting plate.

1. A pre-gapped breaker point assembly for use in a distributor for anignition system of an internal combustion engine and adapted to bemounted in a casing on a movable mounting plate secured in said casingto thereby cooperate with a cam operable by said engine, said pre-gappedbreaker point assembly comprising a frame adapted to be adjustablymounted on said mounting plate and having a first breaker contact pointsecured to a stationary upright flange on said frame and in electricalcontact with said frame and said mounting plate, a second breakercontact point mounted on an arm which is pivotally secured to said frameand resiliently urged to place said second breaker contact point in anormal contacting relationship with said first breaker contact point, acam follower operable between said cam and said arm and operable tointermittently separate said first and said second breaker contactpoints coincident with a high point on said cam and being resilientlyurged toward said cam by said arm, and a spacing block comprised of anabutment surface adapted to bear against at least two high points ofsaid cam and having adjustment means adapted to establish maximumseparation of said first and said second breaker contact points atcoincidence of said cam follower with a high point on said cam, saidadjustment means comprising elongated mounting slots in said spacingblock structure.
 2. The combination of claim 1 wherein said spacingblock is removed after said pre-gapped breaker point assembly is securedto said distributor movable mounting plate.
 3. A pre-gapped breakerpoint assembly for use in a distributor for an ignition system of aninternal combustion engine and adapted to be mounted in a casing on amovable mounting plate secured in said casing to thereby cooperate witha cam operable by said engine, said pre-gapped breaker point assemblycomprising a frame adapted to be adjustably mounted on said mountingplate and having a first bReaker contact point secured to a stationaryupright flange on said frame and in electrical contact with said frameand said mounting plate, a second breaker contact point mounted on anarm which is pivotally secured to said frame and resiliently urged toplace said second breaker contact point in a normal contactingrelationship with said first breaker contact point, a cam followeroperable between said cam and said arm and operable to intermittentlyseparate said first and second breaker contact points coincident with ahigh point on said cam and being resiliently urged toward said cam bysaid arm and a spacing block comprising an abutment surface adapted tobear against at least two high points on said cam to thereby establishmaximum separation of said first and said second breaker contact pointsat coincidence of said cam follower with a high point on said cam. 4.The combination of claim 3 wherein said spacing block is removed aftersaid pre-gapped breaker point assembly is secured to said distributormovable mounting plate.